import numpy as np
import pandas as pd
import matplotlib.pyplot as plt

# ret = np.arange(10)
# print(ret)

# df1 = pd.DataFrame(np.arange(8).reshape(2, 4), index=["thu", "fri"], columns=["open", "high", "low", "close"])
# print(df1)

# x = np.arange(0, 10, 0.1)
# y = np.random.randn(len(x))
# plt.plot(x, y)
# plt.show()

# s = pd.Series(np.random.randn(100).cumsum())
# s.plot()
# plt.show()

df = pd.DataFrame(np.random.randn(100, 4).cumsum(0), columns=["open", "high", "low", "close"],
                  index=np.arange(0, 100, 1))
df.plot()
plt.show()
